1. Field of the Invention
This invention relates generally to oil production and, more specifically, to methods of producing oil reservoirs having a gas cap. In particular, this invention relates to simultaneous production of the gas cap and oil column while introducing an injection fluid at the gas-oil contact.
2. Description of Related Art
The conventional way of producing most oil reservoirs having a gascap is to attempt to produce only from the oil column while keeping the gascap in place so that it expands to provide pressure or energy support. Depending upon the geometry, reservoir dip angle, and oil production rates, gas may either cone down to the oil production wells and/or may breakthrough as a front, leading to substantial increases in the gas-oil ratio of the oil production wells. Direct production from the gas cap is typically delayed until such time that the oil zone is depleted, which may be many years after oil production is initiated. At such time, the gascap is usually directly produced or "blown down."